Researchers from Cornell University have found four key reasons why people make the pledge not to log in to Facebook but ultimately could not resist the allure of Facebook's social network. "The first reason is perceived addiction. Those who feel that Facebook is addictive or habitual were more likely to return," said lead researcher Eric Baumer.

"Another reason is privacy and surveillance. Users who felt their Facebook activity was being monitored were less likely to revert, while those who use Facebook largely to manage how other people think of them are more likely to log back in."

The third reason is subjective mood. In a good mood? You're less likely to renege on your pledge to stay off Facebook," the authors noted. The research group also found that Facebook users were less likely to log back in if they had other social media outlets like Twitter, for instance.

Those who reflected on the appropriate role for technology in their social lives were more likely to revert. "In many of these cases, people returned to Facebook but altered their use, for example, uninstalling the app from their phones, reducing their number of friends or limiting the amount of time spent on the platform," the authors noted.